Rotary unloaders, sometimes called “windmill” unloaders, are used to remove chilled carcasses from poultry chillers. FIG. 1 illustrates a conventional chiller 10 that has an open top, semi-circular tank 12 capable of holding water up to the level 14. An auger 16 that is rotatable about its axial shaft 18 is configured to urge dressed poultry carcasses 22, (also referred as “birds”) from an entry end toward an unloader 20. The unloader 20 is configured to lift the birds 22 from the water and discharge them for packing or further processing, for example into a post chill decontamination tank apparatus.
A post chill decontamination tank apparatus 24 is illustrated in FIG. 2 and includes a tank 25 having an upright entrance wall 26, an opposing upright exit wall 28, and a curved perimeter wall 30 that extends between the entrance wall 26 and the exit wall 28. The walls of the tank 25 define a paddle chamber 33 with an upwardly positioned opening 32 that is formed in the upper perimeter of the tank 25. A paddle assembly 34 is positioned in the tank 25.
The illustrated paddle assembly 34 is structurally and functionally similar to the unloader 20 and includes a hub 36 positioned at a central axis 37 within the paddle chamber 33 of the tank 25. A plurality of arms 38 radiate outwardly from the hub 36 and a flat plate or paddle 42 is fixed to the end of each arm 38 (only one paddle 42 is illustrated in FIG. 2). The paddles 42 are configured to gather birds 22 submerged in the water of the tank 25 and bring them to the top of the tank 25 for discharge through the opening 32. As the hub 36 rotates, the paddles 42 lift the birds 22 submerged in the water within the tank 25.
When a conventional unloader paddle, such as paddle 42 illustrated in FIG. 2, is rotating through the lower portion of the tank 25, the paddle 42 forms an irregular triangular pyramidal space or pocket with the end wall 28 and side wall 30 of the tank 25. The base of the pyramid is defined by a plane roughly perpendicular to the paddle and containing a gathering edge 43 of the paddle 42. Rotation of the paddle assembly gathers birds 22 into this space through the open base of the pyramid. Due to the relatively steep angles at the apex of the pyramid, birds 22 can be packed tightly as the paddle assembly rotates. Excessive pressure at the apex of the pyramid can damage birds even to the extent of breaking bones. This problem is especially severe with relatively small birds that are more delicate and that pack into the pocket in large numbers.